Add extension API test for FileSystem API.

chrome/browser/extensions/extension_fileapi_apitest.cc

Index: chrome/browser/extensions/extension_fileapi_apitest.cc
diff --git a/chrome/browser/extensions/extension_fileapi_apitest.cc b/chrome/browser/extensions/extension_fileapi_apitest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..782a60084cb0e03a388cac46e611a51660e0662a
--- /dev/null
+++ b/chrome/browser/extensions/extension_fileapi_apitest.cc
@@ -0,0 +1,9 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/extensions/extension_apitest.h"
+
+IN_PROC_BROWSER_TEST_F(ExtensionApiTest, FileAPI) {
+  ASSERT_TRUE(RunExtensionTest("fileapi")) << message_;
+}